Triode structure field emission display device using carbon nanotubes and method of fabricating the same

ABSTRACT

A field emission display device and a method of fabricating the same are provided. The field emission display device includes a substrate, a transparent cathode layer, an insulation layer, a gate electrode, a resistance layer, and carbon nanotubes. The transparent cathode layer is deposited on the substrate. The insulation layer is formed on the cathode layer and has a well exposing the cathode layer. The gate electrode is formed on the insulation layer and has an opening corresponding to the well. The resistance layer is formed to surround the surface of the gate electrode and the inner walls of the opening and the well so as to block ultraviolet rays. The carbon nanotube field emitting source is positioned on the exposed cathode layer. An alignment error between the gate electrode and the cathode is removed, and carbon nanotube paste is prevented from remaining during development, thereby preventing current leakage and short circuit between the electrodes and diode emission. Accordingly, the performance of the field emission display device can be improved.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of Korean Patent Application No.2002-3687, filed on Jan. 22, 2002, which is incorporated herein in itsentirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a field emission display device havingcarbon nanotubes and a method of fabricating the same, and moreparticularly, to a field emission display device in which an alignmenterror between a gate electrode and a cathode electrode due tohigh-temperature firing does not occur, and a method of fabricating thesame.

2. Description of the Related Art

Display apparatuses used for personal computers (PCs) and televisionreceivers include cathode-ray tubes, liquid crystal displays (LCDs),plasma display panels (PDPs), and field emission displays (FEDs), whichuse high-speed thermionic emission.

FEDs using carbon nanotubes is much more advantageous than cathode-raytubes in a wide view angle, high resolution, low power, and temperaturestability. Such FEDs can be applied to various fields such as carnavigation apparatuses and view finders of electronic video equipment.Particularly, FEDs can be used as alterative display apparatuses forPCs, personal data assistants (PDAs), medical instruments, highdefinition television (HDTV), and so on.

FIG. 1 is a diagram showing the structure of a conventional fieldemission display device. Referring to FIG. 1, the conventional fieldemission display device includes a substrate 1; an indium tin oxide(ITO) electrode layer 2 formed on the substrate 1; a mask cathode layer3 formed on the ITO electrode layer 2 such that the ITO electrode layer2 is partially exposed; an insulation layer 5 formed on the mask cathodelayer 3 such that a well 8 is formed; a gate electrode 6 formed in theshape of a strip on the insulation layer 5; and an electron emittingsource 31 including carbon nanotubes formed on the ITO electrode layer 2exposed at the bottom of the well 8.

FIGS. 2A through 2J are diagrams showing the stages in a procedure offorming a triode structure before printing carbon nanotube paste in aconventional method of fabricating a field emission display device.

As shown in FIG. 2A, the ITO electrode layer 2 is formed on thesubstrate 1, and the mask electrode layer 3 is deposited on the ITOelectrode layer 2. The substrate 1 is made of glass, and the maskcathode layer 3 is made of a material such as a metal or amorphoussilicon which blocks ultraviolet rays.

As shown in FIG. 2B, photoresist 11-1 is deposited on the mask cathodelayer 3; a mask 71-1 is disposed above the mask cathode layer 3; andultraviolet rays are radiated for exposure. After exposure, etching andcleaning are performed, thereby forming a hole 4 in the mask electrodelayer 3, as shown in FIG. 2C.

As shown in FIG. 2D, the insulation layer 5 is formed on the maskcathode layer 3 and is then fired at a temperature higher than 550° C.for an insulation characteristic. Thereafter, the gate electrode 6 isdeposited on the insulation layer 5, as shown in FIG. 2E.

FIG. 2F shows a photoprocess including exposure, development, etching,and cleaning for patterning the gate electrode 6. Reference numeral 71-2denotes a mask, and reference numeral 11-2 denotes photoresist. If thephotoprocess is completed, the gate electrode 6 having a hole 7, asshown in FIG. 2G. Thereafter, wet or dry etching is performed to etchthe insulation layer 5 and the mask cathode layer 3, thereby forming thewell 8 such that the ITO cathode layer 2 is partially exposed at thebottom of the well 8, as shown in FIG. 2H.

As shown in FIG. 2I, after photoresist 11-3 is deposited and a mask 71-3is disposed, a photoprocess is performed, thereby patterning the gateelectrode 6 in the shape of a strip, as shown in FIG. 2J.

In the above-described conventional method of fabricating a fieldemission display device, the substrate 1 made of glass may be deformedby the heat during high-temperature firing, so an alignment mark may bedisplaced. Due to displacement of the alignment mark, the center of thehole 4 of the mask cathode layer 3 does not exactly meet the center ofthe well 8 after the gate electrode 6 is deposited and patterned, asshown in FIG. 2I. As a result, the electron emitting source 31 isdisplaced from the center of the well 8 to the right or left. Due to analignment error between the gate electrode 6 and the electron emittingsource 31, the gate electrode 6 may become in contact with or very closeto the ITO cathode layer 2, resulting in current leak or a decrease inthe amount of electrons emitted.

FIGS. 2K through 2Q are diagrams showing the stages in a procedure ofmaking carbon nanotubes into an electron emitting source in the triodestructure formed by the procedure including the stages shown in FIGS. 2Athrough 2J in the conventional method.

In injecting carbon nanotube paste into the well 8, a lift-off methodusing a sacrificial layer, a method of performing direct alignment andinjecting carbon nanotube paste, or a rear exposure method can be used.When the method of performing direct alignment and injecting carbonnanotube paste is used, it is difficult to achieve a high aspect ratiodue to an alignment error in equipment and viscosity of a carbonnanotube material. In the rear exposure method, since a sacrificiallayer is not used, a large amount of residues are produced.

Accordingly, a lift-off process using photoresist as a sacrificial layeris generally used, as shown in FIGS. 2K through 2Q, in fabricating anelectron emitting source using carbon nanotube paste.

Referring to FIG. 2K, photoresist 11-4 is deposited on the substrate 1having a triode structure shown in FIG. 2J such that the well 8, theinsulation layer 5, and the gate electrode 6 are covered with thephotoresist 11-4. Thereafter, a photoprocess is performed, therebyetching the photoresist 11-4 only formed in the well 8, except for thephotoresist 11-4 formed on the insulation layer 5 and the gate electrode6, as shown in FIG. 2I.

After the etching step, as shown in FIG. 2M, carbon nanotube paste 12 isinjected into the well 8 by a screen printing method and is deposited onthe entire surface of the photoresist 11-4, and then rear exposure isperformed. Here, the photoresist 11-4 is used as a sacrificial layer.

If the rear exposure is completed, as shown in FIG. 2N, the carbonnanotube paste 12 is divided into exposed carbon nanotube paste 13 andnon-exposed carbon nanotube paste 13′. This happens because the carbonnanotube paste 13′ positioned in front the mask cathode layer 3 is notexposed to ultraviolet rays.

Thereafter, development using a developer such as acetone or Na₂CO₃(0.4% wt) is performed. As a result, the exposed carbon nanotube paste13 remains, but the non-exposed carbon nanotube paste 13′ is lifted offsimultaneously with diffusion of the photoresist 11-4 as a sacrificiallayer to the developer, so carbon nanotube paste 14 having a shape shownin FIG. 2O can be obtained. Here, residue 14′ of the non-exposed carbonnanotube paste 13′ may not dissolves in the developer, or some of theexposed carbon nanotube paste 13 may be exposed to the developer, socarbon nanotube paste may adhere to the gate electrode 6 or theinsulation layer 5.

Thereafter, the resultant structure shown in FIG. 2O is fired at anitrogen atmosphere at a high temperature of about 460° C., therebyshrinking the carbon nanotube paste 14 to form a shrunken carbonnanotube paste 15, as shown in FIG. 2P. Then, the surface of the carbonnanotube paste 15 is mechanically processed to reveal carbon nanotubessunken into the carbon nanotube paste 15, thereby forming the electronemitting source 31, as shown in FIG. 2Q. The residue 14′ still remains.

The residue 14′ may adhere to the surface of the triode structure, asshown in FIG. 2O, causing a defect such as a short circuit betweenelectrodes or a diode emission due to positive voltage.

FIG. 3 shows an alignment error between the gate electrode 6 and theelectron emitting source 31 in a field emission display devicefabricated according to a conventional method shown in FIG. 2D. In FIG.3, the electron emitting source 31 is displaced from the center of thegate electrode 6 to the right.

SUMMARY OF THE INVENTION

The present invention provides a field emission display device in whicha short circuit can be prevented from occurring between a gate electrodeand a cathode by removing an alignment error between the gate electrodeand the carbon nanotubes which may occur during a high-temperaturefiring process.

The present invention also provides a method of fabricating a fieldemission display device, through which a carbon nanotube residue, whichmay cause a short circuit between electrode and diode emission, isprevented from being produced during a carbon nanotube paste developmentprocess.

According to an aspect of the present invention, there is provided afield emission display device including a substrate; a transparentcathode layer which is deposited on the substrate; an insulation layerwhich is formed on the cathode layer and has a well exposing the cathodelayer; a gate electrode which is formed on the insulation layer and hasan opening corresponding to the well; a resistance layer which is formedto surround the surface of the gate electrode and the inner walls of theopening and the well so as to block light; and a carbon nanotube fieldemitting source which is positioned on the exposed cathode layer.

Here, it is preferable that the resistance layer is made of amorphoussilicon.

According to another aspect of the present invention, there is provideda method of fabricating a field emission display device. The methodincludes (a) forming a transparent cathode layer and an insulation layeron a substrate and performing firing; (b) forming a gate electrode onthe insulation layer and patterning the gate electrode to form anopening at the center thereof; (c) etching the insulation layer to forma well corresponding to the opening and patterning the gate electrode ina strip shape; (d) depositing a resistance layer for blocking light onthe surface of the gate electrode and the inner wall of the well andpatterning the resistance layer to expose the cathode layer at thebottom of the well; and (e) forming a carbon nanotube field emittingsource on the exposed cathode layer.

Preferably, the resistance layer is formed of amorphous silicon, and theresistance layer is formed by chemical vapor deposition.

According to still another aspect of the present invention, there isprovided a method of fabricating a field emission display device whichhas a triode-structure composed of an cathode layer formed on asubstrate, an insulation layer formed on the cathode layer such as tohave a well, and a gate electrode formed on the insulation layer such asto have an opening corresponding to the well. The method includes (a)depositing a protective layer such as to surround the insulation layerand the gate electrode and patterning the protective layer such that theprotective layer remains only on the tops of the insulation layer andthe gate electrode; (b) depositing carbon nanotube paste such as thecarbon nanotube paste covers the protective layer and fills the well andthe opening; (c) radiating light at the rear of the substrate to exposethe carbon nanotube paste and the protective layer to the light andperforming development to lift off non-exposed carbon nanotube paste andthe protective layer, thereby forming a carbon nanotube column; and (d)firing the carbon nanotube column to lower it and performing surfacetreatment, thereby forming a field emitting source in which carbonnanotube tips protrude from the surface of the carbon nanotube column.

Preferably, the protective layer is a dry film release (DFR) film.

In step (c), the carbon nanotube paste and the protective layer aresimultaneously lifted off. Alternatively, the non-exposed carbonnanotube paste is first removed using a developer, and then theprotective layer is lifted off.

The carbon nanotube paste and the protective layer are simultaneouslylifted off using a solution of sodium hydroxide.

When the carbon nanotube paste is first removed, preferably, the carbonnanotube paste is removed using a solution of Na₂CO₃, and then theprotective layer is removed using a solution of sodium hydroxide.

The present invention removes an alignment error between a gateelectrode pattern and a cathode pattern, which may occur during ahigh-temperature firing process in fabricating a field emission displaydevice, thereby preventing short circuit between the gate electrode andthe cathode.

In addition, the present invention provides a method of fabricating afield emission display device, in which a protective layer is formed toprotect the surface of the cathode and prevent carbon nanotube pastefrom being remaining during development of the carbon nanotube paste,thereby suppressing short circuit between electrodes and electronemission of an anode.

BRIEF DESCRIPTION OF THE DRAWINGS

The above object and advantages of the present invention will becomemore apparent by describing in detail preferred embodiments thereof withreference to the attached drawings in which:

FIG. 1 is a diagram of a conventional field emission display device;

FIGS. 2A through 2Q are diagrams showing a method of fabricating theconventional field emission display device of FIG. 1;

FIG. 3 is a photograph of a field emission display device fabricated bythe conventional method shown in FIGS. 2A through 2Q;

FIG. 4 is a diagram of a field emission display device according to anembodiment of the present invention;

FIGS. 5A through 5R are diagrams of a method of fabricating a fieldemission display device according to a first embodiment of the presentinvention;

FIG. 6 is a photograph of a field emission display device fabricated bya method of fabricating a field emission display device according to thefirst embodiment of the present invention;

FIGS. 7A through 7H are diagrams of a method of fabricating a fieldemission display device according to a second embodiment of the presentinvention;

FIG. 8 is a photograph of electron emission in the case where liquidphotoresist is used as a sacrificial layer in a method of fabricating afield emission display device according to the second embodiment of thepresent invention; and

FIG. 9 is a photograph of electron emission in the case where a dry filmrelease (DFR) film is used as a sacrificial layer in a method offabricating a field emission display device according to the secondembodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, a field emission display device and a method of fabricatingthe same according to embodiments of the present invention will bedescribed in detail with reference to the attached drawings. The samereference numerals in different drawings represent the same element.

FIG. 4 is a sectional view of a field emission display device accordingto an embodiment of the present invention. Referring to FIG. 4, acathode layer 112 is formed on a substrate 111, and an insulation layer115 having a well 118 is formed on the cathode layer 112. A strip gateelectrode 116 having an opening 118′ expended from the well 118 ispatterned on the insulation layer 115. A resistance layer 120 is formedto surround the gate electrode 116 and the well 118. The cathode layer112 is partially exposed at the bottom of the well 118, and an electronemitting source 131 including a carbon nanotube column and carbonnanotube tips protruding from the carbon nanotube column is formed onthe exposed cathode layer 112.

FIGS. 5A through 5R are diagrams of a method of fabricating the fieldemission display device shown in FIG. 4 according to a first embodimentof the present invention.

As shown in FIG. 5A, the cathode layer 112 of indium tin oxide (ITO) isdeposited on the substrate 111. As described above, the cathode layer112 is formed of a transparent conductive material for rear exposure.

Next, as shown in FIG. 5B, the insulation layer 115 is deposited on thecathode layer 112, and firing is performed at high temperature over 550°C. Unlike a conventional method of fabricating a field emission displaydevice, in the first embodiment of the present invention, a mask cathodelayer is removed; immediately the insulation layer 115 is deposited onthe cathode layer 112; and a firing process is performed before forminga cathode pattern. Accordingly, an alignment error between the cathodepattern and a gate electrode pattern does not occur.

After the firing process, as shown in FIG. 5C, the gate electrode 116 isformed on the insulation layer 115. Thereafter, as shown in FIG. 5D,photoresist 110-1 is deposited on the gate electrode 116; a mask 117-1is disposed on the photoresist 110-1; and the same photoprocessincluding exposure as that described above is performed, thereby forminga gate pattern having a hole 117, as shown in FIG. 5E. The insulationlayer 115 corresponding to the hole 117 is etched, as shown in FIG. 5F,thereby forming a well 118 in which carbon nanotube paste will beprinted later.

FIG. 5G shows a photoprocess including exposure, development, etching,and cleaning in order to make the gate electrode 116 into a patternhaving a strip shape. Reference numeral 110-2 denotes photoresist, andreference numeral 171-2 denotes a mask. The pattern of the gateelectrode 116 formed by the photoprocess is shown in FIG. 5H.

Then, as shown in FIG. 5I, a material such as amorphous silicon whichhas resistance and blocks ultraviolet rays is deposited to surround thegate electrode 116 and the well 118, thereby forming a resistance layer120 blocking ultraviolet rays. The resistance layer 120 is formed usinga chemical vapor deposition (CVD) method which is convenient for stepcoverage.

Next, as shown in FIG. 5J, photoresist 110-3 is deposited, and a mask171-3 is disposed on the photoresist 110-3. Thereafter, a photoprocessincluding exposure and development is performed, thereby exposing thecathode layer 112 at the bottom of the well 118, as shown in FIG. 5K.Subsequently, as shown in FIG. 5L, photoresist 110-4 is deposited on theentire surface of the substrate 111 including the well 118 and theresistance layer 120, and a mask 171-4 is disposed on the photoresist110-4. Then, a photoprocess is performed, thereby patterning thephotoresist 110-4 having a shape shown in FIG. 5M.

As shown in FIG. 5M, the photoresist 110-4 is removed from the well 118and the surface of the cathode layer 112 exposed at the bottom of thewell 118 and remains only on the resistance layer 120 blockingultraviolet rays.

Referring to FIG. 5N, carbon nanotube paste 130 is injected into thewell 118 and is deposited to cover the photoresist 110-4. Then,ultraviolet rays are radiated at the rear of the substrate 111 to exposethe carbon nanotube paste 130. As a result, the carbon nanotube paste130 is divided into exposed carbon nanotube paste 132 and non-exposedcarbon nanotube paste 132′ due to the resistance layer 120 blockingultraviolet rays, as shown in FIG. 5O.

Thereafter, development is performed, thereby removing the non-exposedcarbon nanotube paste 132′ and leaving the exposed carbon nanotube paste132 in the form of a column, as shown in FIG. 5P. Then, a firing processis performed, thereby lowering the exposed carbon nanotube column 133,as shown in FIG. 5Q. Next, a surface process is performed on the exposedcarbon nanotube column 133, thereby forming the electron emitting source131 with arranged carbon nanotube tips having a needle shape, as shownin FIG. 5R.

FIG. 6 is a photograph of a field emission display device fabricated bya method of fabricating a field emission display device according to thefirst embodiment of the present invention. Unlike the conventional fieldemission display device shown in FIG. 3, the electron emitter source 131and the resistance layer 120 are correctly positioned without having analignment error.

A method of fabricating a field emission display device according to thefirst embodiment of the present invention removes an alignment errorbetween a gate electrode pattern and a cathode pattern, which may occurduring a high-temperature firing process in fabricating a large fieldemission display device, thereby preventing electrical short circuitbetween a gate electrode and a cathode which occurs due to electronsemitted from carbon nanotubes. However, when rear exposure is performedusing liquid photoresist as a sacrificial layer and lift-off isperformed as in a conventional method, residue of exposed or non-exposedcarbon nanotube paste may be produced and may result in a fault such asshort circuit between electrodes or emission of electrons due to apositive voltage.

In order to overcome this problem, a method of fabricating a fieldemission display device according to a second embodiment of the presentinvention is provided. In the second embodiment, a protective layer isformed on the surface of a cathode in order to prevent performance frombeing deteriorated due to residue, which is produced during developmentof carbon nanotube paste.

FIGS. 7A through 7H are diagrams of a method of fabricating a fieldemission display device according to the second embodiment of thepresent invention.

FIG. 7A shows a triode structure of a conventional field emissiondisplay device as shown in FIG. 2J. Reference numeral 211 denotes asubstrate. Reference numeral 212 denotes an ITO electrode layer.Reference numeral 213 denotes a mask cathode layer. Reference numeral215 denotes an insulation layer. Reference numeral 216 denotes a gateelectrode. Reference numeral 218 denotes a well.

As shown in FIG. 7B, a material such as a dry film release (DFR) filmwhich is a kind of photoresist and remains during developer treatment isdeposited to cover the insulation layer 215 and the gate electrode 216,thereby forming a protective layer 217, and a mask 271 is disposed onthe protective layer 217. Then, the protective layer 217 is patterned bya photoprocess including exposure and development, thereby forming awell 218′, as shown in FIG. 7C.

After the patterning process, as shown in FIG. 7D, carbon nanotube paste220 is injected into the well 218 and is deposited on the protectivelayer 217.

After the deposition of the carbon nanotube paste 220, rear exposure isperformed by radiating ultraviolet rays at the rear of the substrate211. Then, the ultraviolet rays are blocked by the mask cathode layer213, so carbon nanotube paste 221′ and the protective layer 217 are notexposed to the ultraviolet rays; and the ultraviolet rays pass throughonly the ITO electrode layer 212 from which the mask cathode layer 213is etched, so carbon nanotube paste 221 is exposed to the ultravioletrays, as shown in FIG. 7E.

Thereafter, as shown in FIG. 7F, if development using a developer (forexample, a Na₂CO₃ solution) is performed, the non-exposed carbonnanotube paste 221′ is removed, and the protective layer 217 formed of aDFR film remains. A 4% NaOH solution is used to lift off the protectivelayer 217. The protective layer 217 formed of a DFR film does notdissolve in the NaOH solution and is lifted off from the surface of thesubstrate 11 with its shape maintained, thereby preventing residue ofcarbon nanotube within the solution from remaining. FIG. 7F shows aprocedure of lifting off the protective layer 217 from the gateelectrode 216.

Here, instead of separately removing the non-exposed carbon nanotubepaste 221′ and the protective layer 217, the non-exposed carbon nanotubepaste 221′ and the protective layer 217 can be simultaneously lifted offfrom the exposed carbon nanotube paste 221 and the gate electrode 216 byusing a NaOH solution in step shown in FIG. 7F. This is possible becausethe non-exposed carbon nanotube paste 221′ is chemically combined withthe protective layer 217 and the protective layer 217 is formed offilm-type DFR. In a conventional case using liquid photoresist,non-exposed carbon nanotube paste and photoresist are dispersed within adeveloper and do not chemically combined with each other, so suchsimultaneous lift-off is impossible.

A DFR film is used for a protective layer in the second embodiment ofthe present invention, but any material which chemically combines withcarbon nanotube paste and remains in a solid form within a developer soas to be completely lifted off from a triode structure can be used forthe protective layer.

The residue of carbon nanotube paste occurs in the conventional artbecause non-exposed carbon nanotube paste and photoresist used as asacrificial layer are dispersed within a developer during a lift-offprocess and the carbon nanotube paste at the top of a cathode is exposedto the developer. To overcome these problems, in the present invention,a DFR film which chemically combines with non-exposed carbon nanotubepaste is formed as a protective layer so as to prevent the dispersion ofthe non-exposed carbon nanotube paste within a developer, therebyprotecting a gate electrode layer during a lift-off process. Inaddition, by using the DFR film, exposed carbon nanotube paste can beprevented from directly contacting the developer. Accordingly, a methodof fabricating a field emission display device according to the secondembodiment of the present invention prevents non-exposed carbon nanotubepaste from remaining.

After the lift-off process, a firing process is performed, therebyforming low carbon nanotube column 224, as shown in FIG. 7G. Thereafter,a surface treatment is performed, thereby completing a field emissiondisplay device having needle-type carbon nanotube tips functioning as anelectron emitting source, as shown in FIG. 7H.

A method of fabricating a field emission display device according to thesecond embodiment of the present invention can be applied to a triodestructure according to a method of fabricating a field emission displaydevice according to the first embodiment of the present invention shownin FIG. 5K as well as a conventional triode structure shown in FIG. 2J.

More specifically, after a protective layer made of a DFR film ispatterned to be deposited on the resistance layer 120, which is formedto block ultraviolet rays, in FIG. 5K, the processes shown in FIGS. 7Dthrough 7H are performed, thereby fabricating the field emission displaydevice shown in FIG. 5R. Here, the difference between the first andsecond embodiments is that a field emission display device fabricatedaccording to the first embodiment of the present invention includes aresistance layer instead of a mask cathode layer in order to blockultraviolet rays.

A method of fabricating a field emission display device according to thesecond embodiment of the present invention prevents carbon nanotubepaste from remaining during development of the carbon nanotube paste,thereby protecting the surface of a cathode. Accordingly, short circuitbetween electrodes or diode emission can be prevented.

FIG. 8 is a photograph of electron emission in the case where liquidphotoresist is used as a sacrificial layer in a method of fabricating afield emission display device according to the second embodiment of thepresent invention, and FIG. 9 is a photograph of electron emission inthe case where a DFR film is used as a sacrificial layer in a method offabricating a field emission display device according to the secondembodiment of the present invention.

The photograph of FIG. 9 is brighter than the photograph of FIG. 8, soit can be inferred that the residue of carbon nanotube paste is moreeffectively removed in the case of using the DFR film as the sacrificiallayer than in the case of using the liquid photoresist as thesacrificial layer.

An apparatus and method for fabricating a field emission display deviceaccording to the present invention are advantageous in removing analignment error between a gate electrode and a cathode by performing ahigh-temperature firing process after depositing an insulation layer,thereby preventing current leakage and improving electron emission.

Moreover, a method of fabricating a field emission display deviceaccording to the present invention is advantageous in preventing shortcircuit between electrode or diode emission by preventing carbonnanotube paste from remaining during development.

What is claimed is:
 1. A field emission display device comprising: asubstrate; a transparent cathode layer which is deposited on thesubstrate; an insulation layer which is formed on the cathode layer andhas a well exposing the cathode layer; a gate electrode which is formedon the insulation layer and has an opening corresponding to the well; aresistance layer which is formed to surround the surface of the gateelectrode and the inner walls of the opening and the well so as to blocklight; and a carbon nanotube field emitting source which is positionedon the exposed cathode layer.
 2. The field emission display device ofclaim 1, wherein the resistance layer is made of amorphous silicon. 3.The field emission display device of claim 1, wherein the carbonnanotube field emitting source comprises a carbon nanotube columnpositioned on the exposed cathode layer and carbon nanotube tipsprotruding from the surface of the carbon nanotube column.
 4. A methodof fabricating a field emission display device, comprising: (a)sequentially forming a transparent cathode layer and an insulation layeron a substrate and performing firing; (b) forming a gate electrode onthe insulation layer and patterning the gate electrode to form anopening at the center thereof; (c) etching the insulation layer to forma well corresponding to the opening and patterning the gate electrode ina strip shape; (d) depositing a resistance layer for blocking light onthe surface of the gate electrode and the inner wall of the well andpatterning the resistance layer to expose the cathode layer at thebottom of the well; and (e) forming a carbon nanotube field emittingsource on the exposed cathode layer.
 5. The method of claim 4, whereinthe resistance layer is formed of amorphous silicon.
 6. The method ofclaim 5, wherein in step (d), the resistance layer is formed by chemicalvapor deposition.
 7. The method of claim 4, wherein the carbon nanotubefield emitting source comprises a carbon nanotube column positioned onthe exposed cathode layer and carbon nanotube tips protruding from thesurface of the carbon nanotube column.